Grounding Service Question

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fletcher

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Detroit Michigan
I am a home inspector, not an electrician. I was an electrical apprentice for a year.

Anyway. I was inspectiong a house yesterday and saw a set-up I am not familiar with. The outside of the service looks like this. See photo

http://www.miproperty.com/indigo/electric outside5.JPG


Two #6 stranded copper ground wires come out of the exterior disconnect below the meter. One wire goes to a ground rod outside and the other goes to the water meter.

http://www.miproperty.com/indigo/electricoutside2.JPG

The water meter is properly bonded

http://www.miproperty.com/indigo/electric meter bonded .JPG


The inside service panel does NOT have a #6 copper gound to it. Some of the 12-2 and some of the 14-4 are twisted up which looks a little like #6 but.....I looked very closely. No ground in the panel.

http://www.miproperty.com/indigo/electricservice11.JPG

Question is.....This couldn't be correct, could it????????

See all photos of electric here.

http://www.miproperty.com/indigo/
 
Matt what you have there looks OK.

Outside you have a meter, then the service disconect, the GECs (Grounding electrode conductors) are required to go to the service disconect.

The panel inside is essentially a sub panel and is required to have separate grounding and neutral conductors.

Notice the feeder coming in has two hots, a neutral and a bare equipment grounding conductor.
 
fletcher said:
Why do you think they have a disconnect on the exterior of the house.
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The most common reason for this is that the distance that the conductors run from the point of penetration of the building envelope is greater than the local understanding of what the maximum distance is.

But, even if the distance is short, the service disconnect can still be on the outside.

In my area, the raceway or cable, measured along its length, cannot exceed five feet. If it does, the Service Disconnect has to be outside.

In your pictures, the Service Entrance Conductors exist only between the line side of the outside disconnect (Service Disconnect) and the meter socket and on up the mast to the weatherhead.

The conductors on the load side of the outside disconnect are a feeder.
 
Fletcher,

As a side note, in my area, the bonding of the water meter has the clamps placed on the house side of the house valve and on the street side of the street valve.

Fletcher's picture of the water meter bonding

The two shutoff valves are deemed as likely to be removed as the water meter.

If the clamp placement that you show is common in your area, then there is a different interpretation there, compared to my area.
 
diconnect required

diconnect required

fletcher said:
Why do you think they have a disconnect on the exterior of the house. This is the first time I have ever seen this.
Click to expand...
Im surprised you have not seem this before . I dont think its required by the nec but almost all counties require the disconnect unless now unless the meter and panel are back to back . It looks like the outside grounds are stranded wire , Im almost sure that has to be solid unless larger than #4
 
Matt,
Also as a side note, it appears you have an additional cable from your meter base (besides the one to the outside disconnect). From your picture, I don't know where it terminates. In most jurisdictions, under today's Code, there are a couple of possible violations. Most meter sockets of that size are not rated for two cables to connect and there would need to be a disconnect on that other set of service cables in close proximity to the one shown in the picture.
The "added" service cable was fairly commonplace in this area years ago (usually for heat and/or air), but I'm not sure it was ever "legal".
 
2005 NEC 250.62
Grounding Electrode Conductor Material
The grounding electrode conductor shall be of copper, aluminum, or copper-clad aluminum. The material selected shall be resistant to any corrosive condition existing at the installation or shall be suitably protected against corrosion. The conductor shall be solid or stranded, insulated, covered, or bare.
Click to expand...

2005 NEC 250.118(1)
This conductor shall be solid or stranded; insulated, covered, or bare; and in the form of a wire or a busbar of any shape.
Click to expand...
 
augie47 said:
The "added" service cable was fairly commonplace in this area years ago (usually for heat and/or air. . .
Click to expand...
I see a lot of them for old electric water heater hookups. Many times the water heater hasn't been present for decades.

In my area, an additional meter was extremely common for the "off peak" rate break.

I'm starting to see it come back some now.
 
al hildenbrand said:
As a side note, in my area, the bonding of the water meter has the clamps placed on the house side of the house valve and on the street side of the street valve.
Click to expand...

I have never heard that interpretation before.

The two shutoff valves are deemed as likely to be removed as the water meter.
Click to expand...

IMO that would mean all valve are as likely as a water meter to be replaced.

No big deal, easy to comply, I just find it odd.
 
iwire said:
al hildenbrand said:
As a side note, in my area, the bonding of the water meter has the clamps placed on the house side of the house valve and on the street side of the street valve.
Click to expand...
I have never heard that interpretation before.
al hildenbrand said:
The two shutoff valves are deemed as likely to be removed as the water meter.
Click to expand...
IMO that would mean all valve are as likely as a water meter to be replaced.

No big deal, easy to comply, I just find it odd.
Click to expand...
It occured to me that it might seem odd to some (or much?) of the community.

[hijack] Are there others working in areas that don't worry about bonding around more than the water meter? [/hijack]
 
fletcher said:
I thought the meter was bonded because of the rubber washers at each end of it. Not because it may be removed. The valves are soldered in place.
Click to expand...
I work in the Minneapolis / St. Paul & burbs 7 county area. There are a lot of little municipal and city water companies about. A significant percentage of them have water meter configurations that are electrically continuous, metal to metal. . .yet, jumpering street side of the street valve to the house side of the house valve has been my experience.
 
fletcher said:
Why do you think they have a disconnect on the exterior of the house. This is the first time I have ever seen this.
Click to expand...
This is required by all the fire districts in this area,the fire chief said it was so the fire dept could shut off power to the house before venting.
 
fletcher said:
Why do you think they have a disconnect on the exterior of the house. This is the first time I have ever seen this.
Click to expand...
its a local thing here, any new service 400a or less i believe has to have a disco meterbase combo. they want it like that for fire safety, i dont know makes sense to me.
 
In my experience the requirement of a disconnect nearest the point of entry is subject to the interpretation of the AHJ. There is no actual distance given in the code. I will always do a meter/main combo if the panel is not within 5 feet. I would like to see a less ambigious definition in the code- I dont agree with having to follow someone elses personal opinion.
 
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